The compound that will react most readily with gaseous bromine has the formula

Options

A. `C_(4)H_(10)`
B. `C_(2)H_(4)`
C. `C_(3)H_(6)`
D. `C_(2)H_(6)`

Explanation

To determine the compound that will react most readily with gaseous bromine (Br2), we need to analyze the given options based on their structure and reactivity. Here’s a step-by-step solution:

### Step 1: Identify the Type of Compounds
We need to identify which compounds are alkenes since bromine reacts readily with alkenes due to the presence of a double bond. Alkenes can undergo electrophilic addition reactions with bromine.

### Step 2: Analyze the Given Compounds
The question provides several compounds with different formulas. We need to determine which of these compounds is an alkene and has a double bond.

1. **C4H10**: This is an alkane (butane) with no double bonds.
2. **C2H6**: This is also an alkane (ethane) with no double bonds.
3. **C3H6**: This can be an alkene (propene) with a double bond.

### Step 3: Determine the Reactivity of Alkenes
Among the compounds, only C3H6 (propene) is an alkene. Alkenes react with bromine due to the presence of a double bond, which can be attacked by the electrophilic bromine molecule.

### Step 4: Evaluate the Nucleophilicity
In alkenes, the reactivity can be influenced by the presence of alpha hydrogens. The more alpha hydrogens present, the more nucleophilic the alkene can be.

- For C3H6 (propene), the structure is CH2=CH-CH3. The carbon atoms adjacent to the double bond (alpha carbons) have hydrogen atoms attached:
- The first carbon (CH2) has 2 alpha hydrogens.
- The second carbon (CH) has 1 alpha hydrogen.

Thus, propene has a total of 3 alpha hydrogens, making it more nucleophilic.

### Step 5: Conclusion
Since C3H6 is the only compound that is an alkene and has a significant number of alpha hydrogens, it will react most readily with gaseous bromine.

**Final Answer: C3H6 (Propene)**

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